The Graf Zeppelin, Hindenburg, U.S. Navy Airships, and other Dirigibles

DELAG: The World’s First Airline

DELAG brochure

The world’s first passenger airline, DELAG (Deutsche Luftschiffahrts-Aktiengesellschaft, or German Airship Transportation Corporation Ltd) was established on November 16, 1909, as an offshoot of the Zeppelin Company. The company provided passenger air service until 1935, when its operations were taken over by the newly-formed Deutsche Zeppelin-Reederei.

While many of the early flights were sightseeing tours, the DELAG airship Bodensee began scheduled service between Berlin and southern Germany in 1919. The flight from Berlin to Friedrichshafen took 4-9 hours, compared to 18-24 hours by rail. Bodensee made 103 flights and carried almost 2,500 passengers, 11,000 lbs of mail, and 6,600 lbs of cargo.

DELAG offered the world’s first transatlantic passenger airline service, using LZ-127 Graf Zeppelin to make regular, scheduled flights between Germany and South America beginning in 1931. Graf Zeppelin crossed the South Atlantic 136 times before being retired after the Hindenburg disaster in 1937.

The Origins of DELAG

DELAG’s goal was to commercialize zeppelin travel by providing passenger air service, and to purchase airships built by the Zeppelin Company at a time when support by the military was still uncertain. DELAG was created under the leadership of Zeppelin Company executive Alfred Colsman, who was was married to the daughter of aluminum manufacturer Carl Berg, who supplied aluminum for Count Zeppelin’s airships.

DELAG Before World War I

Between 1910 and the outbreak of World War I in 1914, DELAG zeppelins carried over 34,000 passengers on over 1,500 flights, without a single injury. The majority of the passengers were given free flights to publicize the zeppelin industry (especially members of German royalty, military officers, aristocrats, government officials, and business leaders), but DELAG also carried 10,197 paying passengers before having to cease operations with the beginning of the war.

Passengers aboard a luxurious DELAG zeppelin

DELAG used hangars and landing fields at Frankfurt, Oos (Baden-Baden), Dusseldorf, Lepizig, Postdam, Hamburg, Dresden, Gotha, and elsewhere in Germany (click links for photos), and sold tickets in cooperation with the Hamburg-Amerika steamship line as ticket agent.

DELAG was not able to fulfill its goal of providing regularly scheduled intercity passenger service before 1914, but its pre-war zeppelins introduced thousands of people to air travel.

DELAG After World War I

The revolutionary design of the airship LZ-120 Bodensee, introduced in 1919, finally allowed DELAG to compete with the railways and offer daily passenger service between Friedrichshafen and Berlin. Beginning August 24, 1919, Bodensee flew northbound to Berlin on odd days of the month, and returned south to Friedrichshafen on even days; the flights included a stop at Munich until October 4, 1919.

DELAG acquired a second ship from the Zeppelin Company in 1920; LZ-121 Nordstern was intended to provide international passenger service between Friedrichshafen, Berlin, and Stockholm, but had not yet gone into service when DELAG was forced to cease operations by the Military Inter-Allied Commission of Control estalished under the Treaty of Versailles. DELAG’s two airships were transferred to the Allies as war reparations: LZ-120 Bodensee was given to Italy, and LZ-121 Nordstern was given to France.

DELAG Airships

LZ-7 Deutschland

Deutschland has the distinction of making the first commercial flight of the first commercial aircraft in history, but it was a flight which ended in a crash.

LZ-7 in flight (with thanks to Andreas Horn for the identification)

LZ-7 in flight (with thanks again to Andreas Horn)

Mahogany paneled passenger cabin of LZ-7

LZ-7 departed Dusseldorf on its seventh flight, on June 28, 1910, with Zeppelin Company director Alfred Colsman and a full complement of 23 passengers, mainly journalists covering the flight, enjoying the view from its carpeted, mahogany-paneled, mother-of-pearl-inlayed passenger cabin.

Before long, due to a combination of engine trouble, weather, and the relative inexperience of the ship’s military pilot, LZ-7 crashed into the Teutoburger Forest and was destroyed. Fortunately, there were no serious injuries.

Passenger cabin of LZ-7 (with thanks to Andreas Horn)

Wreckage of LZ-7 at its crash site in the Teutoburger Forest

LZ-8 Deutschland II

LZ-8 was launched March 30, 1911, intended to replace the wrecked LZ-7.

LZ-8 Deutschland II

Unfortunately, LZ-8, also named Deutschland, had a similarly short career. On May 16, 1911, with Hugo Eckener in command of an airship for the first time, LZ-8 had barely left its hangar when it was pulled from its handling crew by a gust of wind and smashed against the roof of the hangar; the passengers and crew were able to escape without injury by climbing down a long fire ladder, but the ship was a total loss.

Wreck of LZ-8 Deutschland II

It has often been said that the almost predictable wreck of LZ-8 — the day’s gusty wind conditions made the flight ill-advised from the start — contributed to Hugo Eckener’s intense caution in the future, and his determination never again to sacrifice safety to pressure from passengers, the public, or any other source.

LZ-10 Schwaben

Schwaben was launched June 26, 1911, and entered passenger service the next month, on July 16, 1911. Frequently commanded by Hugo Eckener, LZ-10 made over 200 flights and carried over 4,300 passengers, mostly on local flights from the hangar at Oos (Baden-Baden), but also from Dusseldorf, Potsdam, and Frankfurt, and occasionally from other cities.

LZ-10 Schwaben in flight

Schwaben was destroyed by a fire and hydrogen explosion at Dusseldorf on June 28, 1912.

LZ-13 Hansa

Hansa made the first international flight by a DELAG ship, traveling from Hamburg to Copenhagen and back on September 19, 1912. Hansa’s first flight was on July 12, 1912, and it carried over 8,200 people on almost 400 flights, mostly from Hamburg and Postdam, but on occassion from other cities such as Leipzig, Gotha, and Berlin. Hansa was last based in Dresden until the outbreak of World War I, when it too was transferred to the Army as a training ship.

Passenger cabin of LZ-13 Hansa

LZ-17 Sachsen

LZ-17 made its first flight on May 13, 1913. Sachsen was the first ship commanded by Ernst Lehmann, who received his airship training in the ship from Hugo Eckener.

During 1913, Sachsen was used mainly for local sightseeing flights at Oos (Baden-Baden) and Leipzig, with occasional flights from Hamburg, Dresden, and other cities.

LZ-17 Sachsen

In 1914 the ship made most of its flights from Hamburg, with additional flights from Potsdam and Leipzig.

Sachsen proved to be an extraordinarily successful ship for DELAG, and carried 9,836 passengers on 419 flights in civilian service.

Sachsen with the zeppelin hangar at Leipzig

With the outbreak of war in August, 1914, Sachsen was transferred to the Army as a training ship, still under the command of Ernst Lehmann, and the leader of the German Navy’s airship service, Peter Strasser, received his training from Eckener and Lehmann aboard Sachsen. Sachsen was later modified to incorporate bomb racks and machine guns and made numerous bombing attacks on targets in Belgium, France, and England. The ship was dismantled in 1916.

LZ-120 Bodensee

The first civilian zeppelin built after the war, LZ-120 was primarily designed to provide fast air transportation between Friedrichshafen and Berlin. Construction was completed within six months, and the ship, named Bodensee, made its first flight on August 20, 1919.

Wind tunnel testing of design for LZ-120 Bodensee

Bodensee’s highly advanced and aerodynamically-determined teardrop shape (which differed greatly from the thin, pencil-like shape of most previous zeppelins) was a great leap forward in zeppelin design, due primarily to the engineering theories of designer Paul Jaray. With its revolutionary design and four 245 hp Maybach MB.IVa engines, LZ-120 Bodensee could reach a speed of 82 MPH.

A relatively short, small ship, Bodensee carried 706,000 cubic feet of hydrogen (later increased to 796,300 during a refit).

Bodensee traveled the 370 miles between Friedrichshafen and Berlin in 4-9 hours, compared to the 18-24 hours it took by rail. With washrooms and a small kitchen for light meals, Bodensee could carry up to 26 passengers in comfort as well as speed. In the three months after the ship’s launch, LZ-120 made 103 flights (almost all of them between Friedrichshafen and Berlin) and carried almost 2,500 passengers, 11,000 lbs of mail, and 6,600 lbs of cargo.

LZ-120 Bodensee

LZ-120 was taken from DELAG by the Military Inter-Allied Commission of Control and delivered to Italy on July 3, 1921, where it was renamed Esperia.

LZ-121 Nordstern

LZ-121 was built to provide the first international passenger zeppelin service, with plans for scheduled flights between Friedrichshafen, Berlin, and Stockholm. LZ-121 was completed in 1920 and christened Nordstern, but the ship was taken from DELAG by the Military Inter-Allied Commission and delivered to France on June 13, 1921, and renamed Méditerranée.

Dan, you are right, and “Luftschifffahrt” is only spelled this way since a spelling reform in 1996. Before, the combination of two words into one would reduce the number of consecutive consonants to two when those consonants were followed by a vowel. The reform in its attempt at dumbing down German did away with such complications.

A wonderful and exiting reading about commercial aviation. Its one of my favorites subjects because I work in the industry. I enjoyed reading about the lives of many German pioneers of aviation, they were the heroes of the time and continue to live in our collective memories.
Thank you
Sal Hernandez

I finished designing the Bodenseee and the schematic drawings, juggling that with school and other things it looks more like the LZ 120 Bodensee crossed with the LZ 129 Hindenburg than either specifically. Hopefully it flies…. Still have to buy the aluminum girders, metallized plastic and helium… And the Remote controller and propellers…

I am planning to build a modified RC Helium Zeppelin this summer, after my trip to Friedrichshafen. It will be a small scale carbon-fiber LZ-120; mine will be designated as the RZ-1 Bodensee (RZ naturally standing for Rigid Zeppelin) and will be the first of 5 of my ZR Project –
RZ-1 Bodensee
RZ-2 Graf Zeppelin
RZ-3 Hindenburg
RZ-4 Schwaben
RZ-5 Zürich

What a novel and revolutionary design. I believe there was another designer of German zeppelins besides the Count who built a teardrop shaped hull with diagonal girders made of plywood. The efficiency of the hull was proven then too.
The Bodensee concept is what I feel is needed now to restart the rigid airship here. Such a ship could carry a small group for day trips, dinner excursions, and if properly equipped, take ten or more in small, Amtrak-like overnight cabin accommodations for weekend jaunts. The ship would be affordable to maintain and build, and using a mix of new and old technology, can be built and more importantly, FAA certified for passenger use. Such a ship could also serve as a test bed for new engine systems, control surfaces, etc. I can see this happening someday soon as long as there’s some little spark somewhere.

I seriously doubt the FAA would certify an airship filled with hydrogen, although considering your average Airbus jet liner is a flying gas can filled with volatile aviation fuel, the hydrogen airship is an even chance. What made them an issue in the 1930’s was the fact the gas cells were made of porous cotton lined with cattle gut membranes for gas tightness. The cells had a short lifespan and became leaky, creating a explosive hydrogen / air mixture in the cells. With today’s Mylar and polymers, gas cells with hydrogen would be far safer and more durable than cotton gas cells. The trick would be to convince the naysayers and doubters at the FAA to certify such a venture. In the meantime, it’ll be helium.

My original comment was a silly play on words from the earlier post. And yet, it does speak to a valid concern.

While, yes, mylar is a fabulous material, it has the notable problem, for this application, that it collects static electricity; the local atoms collect the charge but will not readily conduct it until a gap voltage is released, which happens in a convenient spark. This means that it must be coated with a highly conductive film that transfers the charge to a well grounded sump (a generator or static spar, for example). This is all easily done, but it’s a detail that needs to be addressed, nonetheless.

In that same regard, static-electric build-up is a problem that faces all aircraft. Helicopters are our current greatest sparkers (along with parachutes), and people who jump from them without the aircraft landing will often feel a signficant static discharge. This is not so bad if it passes through your boots, but cargo helicopters employing a cable had, in the past, often injured people who grabbed the cable before it was allowed to touch the ground. Training and some nifty technical advances have mitigated this to a large degree, and that treatment would be well applied to LTA aircraft. The large external surface area of the envelope traveling at moderate speeds will collect considerable charges; thus every touchdown will involve a static discharge. While I believe there to have been significant “anti-static” coatings in the craft interiors walkways, I’m not aware of any mitigation used on the exterior. If I recall correctly, dope had its own static problems.

As it has already been so successfully addressed in other technological arenas, I don’t see that hydrogen, properly managed by current techniques, is itself a problem any greater than many we take for granted daily. Getting that through into a policy or modern practice, however, I see as unlikely for the forseeable future. The perceived cost to benefit is too low to motivate.

But, as wisdom is oft in short supply, we can hope with LTA dreams. (smirk)

Recall that the SR-71 leaked fuel very badly until brought up to temperature by flight, and the F-111 leaked continuously after it dared to land even once. And people still hang-glide—although I don’t expect hang-glider mass transportation any time soon.

Thank you for your reply – a great read!
I heard that helium is in very short supply and may not be available as much as before. This will have a huge impact on the LTA industry to date, and the tactics of the USN during the tight years of the late twenties of having two airships and only one load of helium may happen to the current blimp fleets out there.
If hydrogen can be safely contained in it’s pure form, then a clean means of lift is obtainable. Getting insurance companies to underwrite that would another matter altogether.

Reading “Giants in the Sky” which has much on the Shutte-Lanz airships. They were competitors to the Zeppelin products and were headed by a gentleman with as big an ego as the Count had. That being said, he simply chose spruce plywood to build his airships out of simply to be different than the Count’s zeppelins. Turned out the plywood delaminated in any condition of moisture and girder failures were a common happening during the war years when the Army and Navy flew a few of them. They operated in tandem with the zeppelins under the Kaiser’s flag.

The other company was Schütte-Lanz. Johann Schütte was a professor for naval engineering and Karl Lanz the heir to a successful company for farming equipment. The first ship did have a geodesic frame made from plywood, but later designs used the more conventional technique with vertical frames and horizontal stringers. Designing all the geodesic parts in the time before CAD was a pure nightmare.

I can imagine airships taking their place as vacation or luxury cruises in a lot of places. Think about floating over the Grand Canyon, for instance. I took one of those helicopter flights and I’d sure sign up for an airship flight if I could afford it!

Sure, why not? Florida offers flat land with plenty of lakes for mounting floating hangers that can vane in the wind. Florida would make a good place to fly to the Bahamas to the East, and the Gulf to the West. Such flights could be had in 48 hour lengths with mid-sized ships that would allow for comfort and convenience to the passengers (i.e. enough water for showers, toilets, etc.). Anything longer that that would require a larger ship with far more lifting capability. The weather in that area is fairly even and aside from hurricanes, most of the operations of an airship can be held in Florida.
It is possible that service along the Eastern seaboard of America from New England to Florida, or points beyond in the Caribbean could occur. All there needs to make this happen is investors who want to see these ships grace the skies again.

Very thorough and indepth. Good job brotha. However reading this reminded me of the show Fringe, where in an alternate universe Airships are still a means of mass transportation. I guess the Hindenburg just gave it too much of a bad rep. =/

p.s. Previous post I meant to say LZ 8. LZ 8 was the crash that taught Hugo Eckener to be more cautious about wind conditions. With the right conditions, a Zepplin actually the ideal vehicle for sight seeing. If the Antena that juts off the top of the Empire state building could be moved somehow. The mooring mast below could be used for what it was designed to do. Talk about a fantastic arrival. Can you imagine passing customs on the 100th floor of the iconic skyscraper. Now thats an arrival.

Beside its horrific crash the Hindenburg accident is most likely the singular most massive public relations catastrophe of all time. The Zepplin’s demise was assured on that fiery field in New Jersey. After 1936 no one wanted to fly in a Zep. But there is a lesson in Hugo Eckeners intense caution after the L Z crash. He had felt pressure from passengers to fly that day which he gave in to resulting in a total loss. Life flight helecopters have a methodology that dirigibles should co-opt. Weather conditions play no factor in a helicopter pilots decision to fly. A truly objective 2nd source makes the decision unrelated to type of accident or severity. In this way a pilot does not get influenced to fly in bad conditions to say save a child or making a rash decision. An independent agency etc. could be objective and not influenced by profit or upset sight seers that a Zepplin operator might cave into. And with a better safety record the dirigible industry as a whole would benefit.

Hydrogen only reacts with an oxidizing compound, so what would happen if there was a Zeppelin with hydrogen cells that were surrounded by helium, which doesn’t react with anything? That way, you’d get safety and increased lifting power in the same package. Also, a light frame could be made out of stronger lighter materials like carbon fiber or some other type of light strong material. I mean come on man! This is the future! We can do it!

Dear Dan and nick H
This sounds like a very good idea as hydrogen is one of if not the most abundant lifting gas known to man if such a thing could be used in modern Zeppelins for passenger transport between the continents and cities through out europe and all over the world it would be like nick said safety and effeciencey all in one what would the possibility of that ?? and as for the tests on the hindenburg with this concept i knew nothing of it how did it work and what was the result if either of you could tell me i would be much obliged
cheers
yuors sincerely Jason Wallace

As I understand it, they went so far as to assume they would get Helium so only installed cabins for 50 people. Over the winter 36-37, they decided they would never get He so with the increased lifting power of H2, added 10 more cabins so they could carry 72 passengers. One was a family cabin for 4. But with WWII in the offing, they only sold 36 tickets for the fatal flight.

Yes it would be possible to make a largely advanced Zeppelin’s or even a smaller non-rigged air ship by making the following changes.
1. carbon fiber on certain areas of ship
2. using jet power
3. having computer flight controls
4. better material on the balloons to hold the helium
5. use air planes or helicopters like on the Macon and Akron air ships to leave saving money on docking stations and not having to slow down
6. selling first class inside

The only problem’s is with this is the cost of building the facilities to make them and land them. Also the fact that every one would not trust them because of the Hindenburg EVEN THOUGHT they would be a hundred times as safe as that and be far better planed with 74 years of technological advancement. You might as well try to make a shipping company with a ship called titanic.

Hello:
I know I am late to this discussion, but just as a comparison, how much was a top first class ticket on the Normandie or the Queen Mary? For example, does anyone know how much the Trouville (sp?) suite on the Normandie cost for the famed Rio Cruise?

In any case, I love your web site, and am ecstatic that you are starting to add info on the LZ 130. The last time I saw any image was when I was in high school in the ’70’s, and was allowed a one time visit to the Ohio State Employees Library. The institution contained a book on the history of zeps, and there was one snap of a stateroom, with a woman looking out the large window, her back to the camera. She wore a long dress, and the photo was in black and white. That was it. Needless to say that one view has had me salivating for more.

I will also go on record stating that if someone built a complete replica of the Hindenburg, I would be more than happy to make a voyage, even if she was filled with hydrogen. It doesn’t seem crazy to me at all since I’ve flown many conventional jets filled with jet fuel, and drive in cars filled with gasoline. Similar risks, if not greater, no?

the LZ-129 Hindenburg was originally desighned to be filled with helium, but they couldnt get ahold of enough before the scheduled flight to america, and used hydrogen instead. I was just up last night thinking of how cool it would be to build another helium filled Hindenburg (LZ-129), and started looking it up online. im glad to find that others share my dream… Zepplins have gotten an aweful bad wrap from weather related crashes, But i know technology has advanced enough to prevent that.

But wouldn’t today’s technologies – computer controls, etc. – remove the need for much of the crew? And how much of the crew were cooks and other such service people? Seems like a LZ-120 Bodensee size dirigible, built with modern materials and engines, could provide a train-like speed for metro communities too small to be serviced by rail lines or regular aircraft.

Love your website, and I’m dearly going to have to try the kirschwasser cocktail sometime. I’ve had a love of zeppelins for years, and your website just makes my day. I’m especially pleased with the informative sections on the early and DELAG era zeppelins, although I’m curious about the lack of information on the zeppelins of the Great War. Granted, sites like Trenches on the Web cover them adequately, but you’ve got all the other time frames for the Count’s flying machines. Still, wonderful site. The color pictures of the Hindenburg were very breathtaking!

That would be my ultimate life of travel. a 2010 Version a small boat 60′ feet or so being the control car,and living space able to land in water. The Updated Zepplin Filled with propellant, or an alternative means. all the ammenties and a few small exploring vehicles for land. land, sea, air, truly the ultimate way my wife and I would like to travel. Can you Imagine that. So cool.

Nice site! I’ve been reading about the Lebaudy airship and Alberto Santos Dumont, researching a more-or-less steampunk type of story. I was wondering if you’ve run across anything on the economics of lighter than air travel? Especially in the early years? I’ve read claims that it was fantastically uneconomical, and other accounts that say it was approaching a competitive cost. Also, I’ve been surprised to read how much hydrogen was used. I’d always believed that the Hindenburg was using hydrogen because the US refused to sell the Germans Helium. Is this incorrect? Thanks! –Dan

Every Zeppelin (and other ships of the type for that matter) back in The Day was inflated with hydrogen gas. This was safe if you didn’t light a cigar or traveled with incendiaries, but there were a few highly publicized crashes and explosions along the way (LZ-4, ZR-2, R-101 etc.). So when Zeppelin Company set to work on building the Hindenburg, they wanted to inflate it with the grossly expensive helium gas. The only real seller of helium happened to be the US, and Germany happened to be under Nazi control. The US had also passed the “Helium Control Act of 1927″ which prohibits the US from exporting helium for any reason. Hugo Eckener pleaded with FDR to make an exception but that didn’t work out. Regardless, the Hindenburg was finished but filled with hydrogen, which was far cheaper. I’m sure FDR was kicking himself in the pants when the ship eventually exploded. As for economics, I don’t know, sorry to not answer you completely. I hope this information helps!

You are correct, of course, that the American Helium Control Act of 1927 prevented the exportation of helium (although the law had procedures for exceptions). But while the conventional view is that the U.S. refusal to supply helium was the reason Hindenburg was inflated with hydrogen, John Duggan cites interesting evidence from German history expert and zeppelin scholar Professor Henry Cord Meyer, indicating that the Germans never even applied for an exception to the Helium Control Act. And as Harold Dick commented, by 1936 the Germans had a high level of confidence in their track record of safe operations with hydrogen, and it is unlikely the cash-starved Nazi government would have authorized the release of a large amount of foreign currency to pay for helium in any event.

With regard to the economics, there was a lot written about this by Charles Rosendahl in the 1930s, and the topic is discussed in detail, with supporting figures, by John Duggan. To summarize briefly, the German zeppelins never made a profit, but remember that LZ-127 was designed as a test vehicle and not a commercial enterprise, and that LZ-129 operated alone and had to bear all the fixed cost of the service by itself. If those costs had been spread over several ships making weekly crossings, the service might well have shown an operating profit.

Just a thought from a non-economist on the economic matter. At least according to Wikepedia, the Hindenburg had 61 crew members and only 36 passengers when it burned. That’s essentially a 2:1 ratio in favor of crew. Granted, Hindenburg had a capacity of 70 passengers. But that’s still pretty bad, it’s still about a 1:1 ratio.

Imagine Lufthansa today putting an airbus up with, say 125 paying passengers and 125 employees, and then saying they might make money if only they could put enough flights like this into the air.

Hindenburg actually had an operational crew of 40 (the 61 crewmembers on the final flight included 21 men who were being trained for service on the new LZ-130, which was under construction), but Jim’s basic point is completely correct. And in addition to the 40 members of the aircrew, large passenger zeppelins also required hundreds of men on the ground to assist with landing operations, and huge and expensive infrastructure such as hangars, mooring masts, and other ground equipment.

But at the time, dividing those costs among several airships could have made zeppelin operations profitable when you consider how much the DZR was able to charge for passengers, mail, and freight. The Hindenburg was the fastest way to cross the Atlantic (twice as fast as any ocean liner) and was therefore able to command huge fares. A round-trip ticket cost $810 in 1937; the average American income was $890 per year at the time, and a 1937 Ford cost $850. ($810 in 1937 dollars would be worth between $12,000 and $60,000 today, depending on how you measure it.) And in addition to passenger fares, the DZR could have earned tens of thousands of dollars from carrying mail and freight.

But operating an aircraft like Hindenburg was still tremendously expensive, and it would have been difficult for the DZR to compete economically even with the airliners available later in the 1930’s, such as the Boeing 314 clippers operated by Pan Am, which needed a crew of only 10 to transport 40 passengers across the Atlantic.

But of course the supply/demand curve works for fares. If they had greatly increased the number of passenger trips available, it is unlikely that they could have kept prices as high. Those prices couldn’t really be justified for a “mode of transportation,” rather as an incredibly exclusive and expensive excursion. They were really flying “cruise ships” rather than flying liners.

I could think of a number of reasons why it would be cheaper to operate today. Electric winches could replace a lot of the grounding crew. Compressors could compress the helium in for landing and decompress for takeoff, instead of venting it and refilling. Also, helium is much cheaper today, and there are a million polymers and plastics that could replace the cow-intestine helium bags, and hull skin. If I had the money, i would start a zepplin airtravel company. I cant see it being practical for transcontenental travel, (since jets are so much faster) but it could be like a recreational cruiseship for the air! to fly over america at 60mph or so an be just a couple thousand feet above the ground.